Valneva stock plummeted Friday after Pfizer said it will drop roughly half of the participants enrolled in the companies' Lyme disease vaccine study.
The decision comes after Pfizer found violations of "good clinical practice" rules at study sites run by a third-party operator. These rules safeguard ethical and scientific standards of clinical studies. Pfizer and Valneva noted the decision isn't due to any safety concerns with the vaccine and was not prompted by any side effects.
Now, Pfizer and Valneva could run behind schedule in enrolling the 18,000 participants needed for the test. Contracted through tick bites, Lyme disease can cause a fever, headache, fatigue and a skin rash, according to the Centers for Disease Control and Prevention. If left untreated, it can spread to the heart and nervous system.
"Once Pfizer learned of potential violations of GCP, it conducted a thorough review of the operations and data collection at the clinical trial sites run by the third party and followed standard operating safeguards to determine the correct course of action," the companies said in a written statement.
On today's stock market, Valneva stock dropped 7.6% and closed at 12.62. Pfizer stock rose a fraction, ending the regular session at 43.21.
Valneva Stock Hits 50-Day Ceiling
Pfizer and Valneva inked a $308 million collaboration deal in 2020 for the experimental Lyme disease vaccine called VLA15. Valneva also is eligible for tiered royalties on sales starting at 19%. Last June, Pfizer doubled down on its bet with a $95 million investment in Valneva stock.
The companies then started their Phase 3 study in Lyme disease in the third quarter. Their goal is to enroll 18,000 participants across multiple countries in areas of endemic Lyme disease. Further, participants should have lifestyles that put them at increased risk of contracting Lyme disease, including working outdoors or recreational hiking.
They planned to finish enrolling patients by the end of 2024, according to Clinicaltrials.gov. Pfizer says it still plans to submit approval requests in the U.S. and Europe in 2025. But the news Friday sent Valneva careening lower.
"Integrity of data collected un clinical trials is critical to provide evidence and confidence in a potential vaccine or medicine's safety and efficacy," the companies said in their statement. "Pfizer and Valneva are committed to collecting robust data needed for potential regulatory submission of VLA15."
Valneva stock made a run at its 50-day moving average on Thursday, but remained under that ceiling, according to MarketSmith.com.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
